Add limoncello, cranberry juice, vodka (if using), and cream. Shake well until cold.
Strain into a chilled champagne flute or coupe glass.
Slowly top with prosecco to keep bubbles lively.
Garnish with cranberries or a lemon twist.
Notes
For a lighter version, skip the cream and use only limoncello and prosecco. Use super cold prosecco for the best fizz. Unsweetened cranberry juice keeps this crisp and bright, not overly sweet.